KR20110025571A - Laundry machine - Google Patents

Abstract

PURPOSE: A washing machine is provided to optimize the air flow for a cooling stator. CONSTITUTION: A first and second cooling holes(218a,218b) is systemically matched base on a central line(220). The central line is expanded to a radius direction in a center of a base(212). A first blade(217a) generates airflow to an internal circumference direction of a rotor. The first blade flows in air to inside of the rotor through the first cooling hole. The first blade and second blade(217b) are symmetrical matched based on the central line. The second blade flows out air to external side of the rotor through the second cooling hole.

Description

Washing machine

The present invention relates to a motor and a washing machine including the same, and more particularly, to a motor directly connected to a drum and a washing apparatus including the same.

Recently, many washing machines, particularly drum type washing machines, have been used. In the drum type washing machine, the drum is placed horizontally and rotates about the horizontal axis to wash laundry. Such a drum type washing machine is generally referred to as a front loading type washing machine because laundry can be put into or collected from the drum through the front opening of the cabinet.

The drum washing machine is provided with a tub for storing wash water, and a drum rotating inside the tub. A through hole is formed in the outer wall of the drum so that the wash water flows in the tub and the drum.

A motor is used to rotate the drum, and a brushless DC (BLDC) motor is often used because a lot of torque is generated and complicated control is required when the drum is rotated. In addition, such a motor uses many outer rotor type motors in which the rotor rotates outside the stator.

In addition, the rotational force of the rotor is not used to rotate the drum by using a pulley or the like, and a lot of forms of directly rotating the drum are used. Therefore, a washing machine having such a driving form is also referred to as a direct drum washing machine. In the direct drum washing machine, the stator is fixed to the rear wall of the tub, and the rotational force of the rotor is transmitted directly to the drum through the drum shaft.

Recently, large-capacity drums are preferred, and the drum is rotating in various forms for washing according to various washing demands. Coils are wound around the stator of the motor, and it is no exaggeration to say that the load on the motor is gradually increased according to the change. Therefore, it is necessary to effectively cool the heat generated in the stator, in particular, the stator coil, to further improve the durability and reliability of the motor, thereby providing a washing machine capable of meeting various demands of the user.

On the other hand, many inventions have been disclosed for the cooling characteristics of such a direct type motor. For example, the invention described in Korean Patent Application Publication No. 10-2006-0054531 filed by the present applicant relates to a motor for a washing machine in which a cooling hole and a cooling fin are formed in a rotor frame. As the rotor rotates, cooling fins generate a flow of air and air is discharged through the cooling holes.

However, such a motor has a problem that cooling is effective only for rotation in a specific direction and cooling is not effective for rotation in the opposite direction. In addition, the viewpoint of the flow of air is mainly considered for the cooling of the stator, and thus does not consider the flow direction of the air and the cooling effect thereof.

Recently, motors and washing machines have been disclosed in which the stator coil is replaced with aluminum instead of copper due to a rise in copper prices. Aluminum has a relatively higher heat generation rate because of its higher electrical resistance than copper. Therefore, it would be further desirable to improve the cooling performance of the stator in motors and washing machines using aluminum.

The present invention basically aims to solve the problems of the above-described motor and washing machine.

An object of the present invention is to provide a motor and a washing machine including the same that can effectively cool the stator in response to various loads. In particular, it is an object of the present invention to provide a motor and a washing machine that can effectively guarantee the cooling of the stator in a washing machine in which the dehydration direction can be performed in both directions.

In addition, an object of the present invention is to provide a washing machine that is easier to manufacture by minimizing a change in vibration characteristics that may be caused by a motor.

An object of the present invention is to provide a motor and a washing machine that can satisfy the requirements of the motor and washing machine using an aluminum coil by optimizing the flow of air for cooling the stator.

In addition, an object of the present invention is to provide a washing apparatus capable of repeatedly washing and dehydrating the rotation and rapid braking of the drum, thereby satisfying the cooling performance.

In order to achieve the above object, the present invention, a tub; A drum rotatably provided in the tub; A motor including a stator fixed to the rear wall of the tub, a rotor rotating the outside of the stator to rotate the drum, and a cooling unit provided at the base of the rotor to generate air flow during rotation to cool the stator; And a controller configured to rotate the motor so that dehydration proceeds from the drum regardless of the direction of rotation of the motor, wherein the cooling unit is provided on both sides of the center line extending radially from the center of the base. A first cooling hole and a second cooling hole provided to be symmetrical with each other at a predetermined distance; A first blade configured to generate air flow in an inner circumferential direction of the rotor and allow air to flow into the rotor through the first cooling hole; And a second blade provided to be symmetrical with the first blade based on the middle wire to allow air to flow out of the rotor through the second cooling hole.

The invention also provides a tub; A drum rotatably provided in the tub; A motor including a stator fixed to the rear wall of the tub, a rotor rotating outside the stator to rotate the drum, and a cooling unit provided at a base of the rotor to generate air flow during rotation; And a controller configured to control washing and rinsing of the drum by repeating sudden stops due to rotation and reverse braking of the motor, wherein the cooling unit is based on a center line extending radially from the center of the base. A first cooling hole and a second cooling hole provided to be symmetrical with each other at a predetermined distance from both sides; A first blade configured to generate air flow in an inner circumferential direction of the rotor and allow air to flow into the rotor through the first cooling hole; And a second blade provided to be symmetrical with the first blade based on the center line so that air flows out of the rotor through the second cooling hole.

The cooling unit may be provided in plurality in the circumferential direction. And, it is preferably formed to be symmetrical along the circumferential direction. Therefore, the vibration and cooling characteristics are the same regardless of whether they rotate clockwise or counterclockwise.

In addition, since the inflow and outflow of air occurs based on the center line, cold air may be smoothly introduced to cool the stator, and the heat exchanger may sufficiently exchange heat with the stator, and the heat exchanged hot air may be smoothly discharged. Therefore, effective cooling is possible regardless of the rotation direction.

The present invention may be further embodied through the embodiments described in the detailed description, but is not limited to the embodiments.

According to the present invention, an object of the present invention is to provide a motor capable of effectively cooling a stator and a washing machine including the same. In particular, the present invention can provide a motor and a washing machine that can effectively ensure cooling of the stator in the washing machine in which the dehydration direction can be performed in both directions.

In addition, according to the present invention it is possible to provide a washing machine that is easier to manufacture by minimizing the change in vibration characteristics that may be caused by the motor.

According to the present invention, by optimizing the flow of air for cooling the stator, it is possible to provide a motor and a washing machine capable of satisfying the required conditions in a motor and a washing machine using an aluminum coil.

In addition, according to the present invention, the rotation and rapid braking of the drum may be repeated so that washing or dehydration may be performed, thereby providing a washing apparatus capable of satisfying cooling performance.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosure may be made thorough and complete, and to fully convey the spirit of the present invention to those skilled in the art. Like numbers refer to like elements throughout.

1 is a configuration diagram schematically showing an example of a drum washing machine according to an embodiment of the present invention.

Referring to FIG. 1, a drum washing machine includes a case 10 forming an appearance, a tub 20 installed in the case 10 and receiving wash water, and a cylindrical shape rotatably installed in the tub 20. The drum 30 is installed on the rear side of the tub 20 and is made of a large motor 40 for generating a rotational force by receiving power.

The door 12 is installed at the center of the front of the case 10 so that laundry can be put into the drum 30 and taken out. The door 12 is hinged to the case 10 to open and close.

A hanging spring 22 through which the tub 20 is suspended is installed between an upper side of the outer peripheral surface of the tub 20 and an inner side of the upper surface of the case 10, and a lower side of the outer peripheral surface of the tub 20 and the case 10. The damper 24 is provided between the lower surfaces to damp the vibration of the tub 20 generated during dehydration.

A gasket 26 is provided between the door 12 and the tub 20 to prevent the leakage of the wash water, thereby maintaining airtightness.

On the inner circumferential surface of the drum 30, lifts 32 are formed at regular intervals along the circumferential direction to agitate laundry and washing water.

In addition, the motor 40 is composed of a stator 42 fixed to the rear of the tub 20 and a rotor 44 installed outside the stator 42, and the drum shaft 46 includes the rotor 44. And the drum 30 is directly connected to transmit the rotational force to the drum 30.

On the other hand, the front of the drum 30 is formed in a ring shape in the circumferential direction and the balancer 50 is provided in the interior having a predetermined width.

The front of the cabinet 10 is provided with a control panel 11 for interfacing with the user, the control panel 100 may be provided with a control unit (not shown) for controlling the operation of the drum washing machine.

Drum washing machine according to the invention is preferably made of dehydration in both directions. That is, the control unit does not control the dehydration to occur only in a specific direction, it is preferable to control so that the dehydration in any direction clockwise or counterclockwise. That is, the dehydration direction is determined at random.

The control unit does not control the drum to be dewatering RPM immediately for dewatering. In other words, in order to minimize vibration and noise, dehydration entry is performed to perform defoaming or eccentricity detection, and if dehydration entry conditions are satisfied, the dehydration RPM is accelerated to control dehydration.

If dehydration proceeds in only one direction, there is a problem in that the dehydration time increases. This is because if the drum is not rotating in the specific dehydration direction even if the dehydration entry condition is satisfied, the dehydration proceeds only when the drum is rotated in the specific dehydration direction by repeating the previous process again. Therefore, when the drum washing machine is dehydrated in both directions, it is possible to reduce the dehydration time.

In most cases, however, cooling of the stator is most necessary when dewatering. Therefore, even if dehydration takes place in any direction, a motor capable of effectively cooling the stator is required. This is because the conventional motor is designed to increase the cooling effect only when dehydration occurs in a specific direction.

On the other hand, the washing machine has inherent vibration characteristics. That is, it has an inherent low speed resonance RPM and a high speed resonance RPM, and when the drum rotation speed is equal to the resonance RPM, vibration and noise are significantly increased. Therefore, in general, when performing dehydration of the washing machine, it is controlled to avoid such a resonant RPM, and is also controlled to escape the resonant RPM very quickly. In general, since the low speed resonant RPM is higher than the washing RPM, it is not a problem during washing, and it is considered only when dewatering. In general, dehydration is performed by rotating the drum at an RPM outside the resonant RPM.

When the dehydration direction of the washing machine is changed due to the vibration characteristics, the vibration characteristics of the washing machine may vary. This may occur as the bidirectional rotational characteristics of the motor change. That is, according to the conventional motor described above, the air flow pattern is different depending on the rotation direction. Therefore, the vibration and vibration characteristics as well as cooling characteristics during bidirectional dehydration are very difficult to design and control.

For example, even if all other conditions are the same, when the motor is dehydrated by rotating the motor at 1000 RPM, the amount of current applied may vary according to the dehydration direction. This is because the rotational resistance may vary depending on the dehydration direction because the shape of the rotor frame is not symmetric regardless of the dehydration direction. If the same amount of current is applied, the dehydration performance may vary depending on the dehydration direction, which may lower the reliability of the product.

Therefore, when the motor is controlled to perform dehydration at least in both directions, it is preferable to eliminate the problem that the vibration characteristics or the rotation characteristics of the washing machine vary according to the rotation direction of the motor. This will provide a washing machine easier to design and control, and easy to manufacture.

On the other hand, in general, the drum washing machine performs washing or rinsing while the drum is tumbling motion. Tumbling motion is a motion in which the drum rotates in one direction and lifts and drops the laundry. For example, after the drum is continuously rotated clockwise for 20 seconds and stopped for 10 seconds, the pattern is repeated for 10 seconds after the drum is continuously rotated counterclockwise for 20 seconds. Here, the sum of the ON time and the OFF time of the motor for drum driving is 30 seconds, and the ON time of the drum is 20 seconds. Therefore, the actuation rate may be 20/30. In this tumbling motion, clockwise rotation and counterclockwise rotation are alternately performed.

This tumbling motion is generated because the centrifugal force generated by the rotation of the drum is smaller than the gravity 1G. The drum rotation speed in the tumbling motion will depend on the inner diameter of the drum, but can be determined to be around 43 RPM. Therefore, the load on the motor when rotating the drum in tumbling motion is not so great. For this reason, as described above, it can be said that the load on the motor is considered only during dehydration, not during washing or rinsing.

However, in order to further improve washing or rinsing performance, it is necessary to drive the drum in a motion other than tumbling motion. In other words, it is necessary to further increase the washing or rinsing performance by applying a stronger mechanical force to the laundry or the wash water. In addition, it is desirable to allow the user to visually recognize that washing and rinsing are sufficiently performed through the drum driving motion.

Hereinafter, a step motion and a scrub motion different from the tumbling motion will be described in detail with reference to FIGS. 2 and 3.

2 is a diagram showing step motion over time. The step motion is a motion in which the motor 40 rotates the drum 30 in one direction but the laundry on the inner circumferential surface of the drum falls from the highest point in the drum's rotational direction (a position of about 180 degrees) to the lowest point of the drum.

When the motor 40 rotates the drum 130 at about 60 RPM or more, the laundry can be rotated without dropping by centrifugal force. The step motion allows the drum to move at a speed such that the laundry does not fall from the drum inner circumferential surface due to the centrifugal force. After rotating, the drum is braked to maximize the impact force on the laundry.

In the step motion, the motor 40 rotates the drum at a speed at which the laundry does not fall from the outer circumferential surface of the drum by centrifugal force (about 60 RPM or more), and the laundry is located near the highest point of the drum (180 degrees in the rotational direction). The reverse torque is controlled to supply the drum 130.

Therefore, the laundry rises in the rotational direction of the drum at the lowest point of the drum 30 and then falls from the highest point of the drum 30 to the lowest point at the moment the drum stops due to the reverse torque of the motor 40. Is a motion of washing or rinsing by the impact force caused by the process of the laundry falling inside the drum to the maximum drop. The mechanical force generated by this step motion is larger than the tumbling motion described above.

Visually, the step motion is a form in which the drum moves clockwise from the lowest point of the drum to the highest point of the drum after passing from the third quadrant to the highest point of the drum and then suddenly falls off the inner peripheral surface of the drum to the lowest point of the drum. Therefore, since the distance falling in the drum in the step motion is the largest, it is possible to more effectively provide a mechanical force when the amount of small amount.

On the other hand, the motor 140 is preferably reversed braking for braking the drum. The reversed phase braking is a method of braking the motor by generating a rotational force in a direction opposite to that in which the motor is rotating. The phase of the current supplied to the motor can be reversed to induce a rotation force opposite to the direction in which the motor is rotating, and the reverse phase braking enables rapid braking of the motor. Accordingly, the reversed braking is the most suitable braking method for the step motion which gives a strong impact on the laundry.

Thereafter, the motor 40 again applies torque to the drum 30 to raise the laundry at the lowest point of the drum to the highest point. That is, after the torque is applied to rotate clockwise, the torque is momentarily stopped by applying the torque to rotate in the counterclockwise direction, and then the torque is applied to rotate in the clockwise direction.

As a result, the step motion is a motion of washing the laundry and the laundry introduced into the through hole of the drum during the rotation of the drum, and washing the laundry by the impact force when the laundry is located at the top of the drum.

This step motion is performed in a clockwise direction at a predetermined actual rate, and then counterclockwise at a predetermined actual rate. This pattern may be performed in the same way as tumbling.

FIG. 3 shows scrub motion over time. FIG.

The scrub motion is a motion in which the motor 40 rotates the drum 30 in both directions, and the laundry is dropped at a position about 90 degrees or more in the rotational direction of the drum.

That is, when the motor 40 rotates the drum 30 counterclockwise to about 60 RPM or more, the laundry located at the lowest point of the drum 130 rises a predetermined height counterclockwise. At this time, the motor is to stop the rotation of the drum by providing a reverse torque to the drum after the laundry has passed the counterclockwise position of about 90 degrees. Then, the laundry on the inner circumferential surface of the drum drops rapidly.

Thereafter, the motor 140 rotates the drum clockwise at about 60 RPM to raise the dropped laundry a predetermined height clockwise. The motor 140 stops rotation of the drum by providing reverse torque to the drum 130 when the laundry passes through the clockwise 90 degree position of the drum. Therefore, the laundry on the inner circumferential surface of the drum falls to the lowest point of the drum at a position 90 degrees or more clockwise of the drum.

Thus, the scrub motion is to wash the laundry by dropping the laundry sharply at a predetermined height. On the other hand, the motor 140 is preferably reversed braking for braking the drum.

Since the direction of rotation of the drum is sharply switched, the laundry does not deviate greatly from the inner circumferential surface of the drum, thereby obtaining a very strong rubbing effect. The scrub motion is a form in which the laundry moved to the part of the second quadrant after the third quadrant drops sharply and moves again to the part of the first quadrant after the fourth quadrant. Therefore, it can be said that the laundry which rises visually descends along the inner peripheral surface of a drum.

Through the above-described step motion and scrub motion, the flow pattern of the laundry inside the drum is very different from the tumbling motion. That is, due to the rotation and sudden stop, the flow of the laundry changes drastically, so that a larger mechanical force can be applied to the laundry and the wash water.

Meanwhile, in the step motion and the scrub motion, the reverse braking timing of the motor 140 is closely related to the position of the laundry in the drum 130, and thus, a device capable of determining or predicting the position of the laundry is preferably provided. An example may be a sensing device having a Hall effect sensor capable of determining a rotation angle.

Through the Hall sensor, the controller may determine the rotation direction as well as the rotation angle of the rotor. Details thereof will be apparent to those skilled in the art, and thus a detailed description thereof will be omitted.

The control unit may determine the rotational angle of the drum through the sensing device, and when the drum detects that the drum rotates by a predetermined angle, the controller controls the motor 140 to reversely brake.

The step motion and scrub motion can be said to be a drum driving motion is very desirable for improving the washing performance or rinsing performance. However, the drum rotation speed is larger than the general tumbling motion. Then, the rotation and sudden stop are repeated, which causes a large mechanical load on the motor. In addition, the phase of the applied current is changed instantaneously for the sudden stop of the drum. Therefore, there is a fear that excessive heat is generated in the stator coil.

In addition, the step motion and the scrub motion are performed while alternating clockwise rotation and counterclockwise rotation of the drum.

For this reason, when washing or rinsing in step motion and scrub motion, it is necessary to ensure the same cooling performance regardless of the rotation direction of the motor. That is, when washing or rinsing is performed in step motion or scrub motion, it is necessary to consider the cooling performance of the motor when washing or rinsing as well as during dehydration.

Therefore, embodiments of the present invention described below are not only a washing device in which the rotation direction of the drum for dehydration is random, but also a step motion in which rapid braking occurs due to reverse braking while rotating clockwise and counterclockwise during washing or rinsing. It is very desirable for a washing machine in which scrub motion is performed. Of course, in either case, the rotation of the drum is controlled by the control unit.

Hereinafter, with reference to Figures 4 and 5 will be described in detail an embodiment of a motor that can be applied to the washing apparatus according to the present invention.

First, the stator of the motor will be described in detail with reference to FIG. 4.

The stator 42 may include a stator core 110, an upper insulator 120, and a lower insulator 130.

The stator core 110 includes an annular back yoke 111 and a tooth 112 protruding radially outward along an outer circumference of the back yoke.

The stator core 110 may be formed by punching and stacking steel sheets. However, in the case of using such a method, the steel sheet fragments, etc., generated in a circular shape inside are not necessary, and there is much room for waste of materials. Therefore, the strip-shaped yoke and the teeth vertically protruding from the back yoke are preferably bent and spirally stacked to form a spiral core. This spiral core form is shown in FIG. 2.

In addition, the stacked annular back yoke 111 is formed with a caulking portion 113 such that each layer is coupled to each other to form a stator core integrally.

A coil (not shown) is wound around the tooth 112. However, since the tooth is generally a conductor material, an insulator for insulation is generally provided between the tooth and the coil. Therefore, in the present invention, the insulators 120 and 130 are provided on the upper and lower portions of the stator core 110, respectively. That is, the upper insulator 120 and the lower insulator 130 are combined with the stator core 110 to surround the stator core. At this time, a coil is wound around the windings 121 and 131 surrounding the teeth 112.

However, unlike FIG. 4, the insulators 120 and 130 may be integrally formed with the stator core 110. For example, it is possible that the stator core is insert injection molded and formed integrally with the insulator.

Meanwhile, fastening bosses 125 and 135 protruding in the radial direction are formed inside the insulators 120 and 130, and the stator 100 is positioned on the rear wall surface of the tub of the drum washing machine (not shown). Fastening holes 126 and 136 are formed to be fixed. Of course, the fastening bosses 125 and 135 may not necessarily be configured to be fixed to the tub, and may be fixedly coupled to a bracket (not shown) or a motor housing (not shown) forming the outer shape of the motor according to the application example. It may be a configuration for.

That is, the fastening hole 126 of the upper insulator and the fastening hole 136 of the lower insulator correspond to each other when the upper insulator, the stator core, and the lower insulator are combined to form one fastening hole. The entire stator is fixed to the tub or the like through a bolt (not shown) in the fastening hole.

In addition, a positioning protrusion 127 may be formed near the fastening hole 126 of the upper insulator. That is, the positioning protrusion may be first inserted into a groove (not shown) formed in a tub or the like to determine the position of the stator 100, and then the stator 100 may be fixed using the above-described bolt or the like.

Meanwhile, coils corresponding to each of u, v, and w phases may be wound in the stator illustrated in FIG. 4. One coil may be wound around one tooth such that one tooth has one magnetic pole. This is called the concentration zone. The more stator stimulation, the lower the maximum rotation speed of the rotor. Therefore, it is easy to control the motor, and the maximum torque can also be relatively large.

First, when the winding of the u-phase coil is terminated in one tooth, the coil is wound around the coil winding ribs 122 formed in the upper insulator and fixed, and then wound again in the next tooth after crossing two neighboring teeth. The start and end of this coil are located at the tap terminal 128 and the neutral tap terminal 129 for power connection, respectively.

Here, the connector 140 is coupled to the tap terminal for power connection, and power of three phases is applied to the coils of each of u, v, and w phases. In addition, the ends of the coils of each phase are all electrically connected to each other at the neutral point terminal terminal 129 to form a neutral point.

Here, the tab terminals 128 and 129 are formed of an insulating material, preferably, integrally with the insulator.

Meanwhile, the hall sensor assembly 141 is fixed to one side of the tap terminal, that is, the tap terminal 128 for power connection and the neutral tap terminal. Through the Hall sensor assembly, it is possible to control the rotation speed and torque of the rotor by controlling the phase and current strength of the applied current by sensing the position and / or speed of the rotor to be described later. And, it is possible to control the timing of reversed braking.

Insulator ribs 123 are formed in the radially inner side of the coil winding rib 122 along the circumferential direction. Of course, such insulator ribs 123 are formed in the lower insulator as well as the upper insulator. The insulator rib 123 is formed to a predetermined height or more to perform a function of blocking the flow of moisture inside the insulator to the windings 121 and 131.

In addition, the insulator rib 123 is preferably formed to be higher than the height of the coil winding. This is because the coil may be damaged when the stator 100 is handled, for example, in a peripheral object or the like. That is, when placed on the floor, only the insulator rib 123 is in contact with the floor, and the coil is not in contact with the floor, thereby preventing damage to the coil in advance.

Next, the rotor will be described in detail with reference to FIG. 5.

The rotor 44 includes a rotor frame 210 and a magnet 216.

The rotor frame 210 includes a base 212 and a side wall portion 211 formed on the outside of the base, which may be formed by pressing a single iron plate. Here, a plurality of magnets are provided inside the sidewall portion along the circumferential direction. These magnets are magnetized to the north pole and the south pole alternately along the circumferential direction.

The side wall portion 211 performs a back yoke function of forming a magnetic path.

Of course, the rotor frame described above may be formed by injection, in which case the annular magnetic back yoke should be provided separately.

In addition, the center portion of the base 212 is formed with a hub portion 213 protruded upward for rigid reinforcement of the base. The hub portion 213 has a through hole 219 formed at the center thereof, and a drum shaft 46 (see FIG. 1) is located at this portion. The drum shaft and the hub portion 213 are connected to each other using a connector, not shown. Therefore, as the rotor is rotated, the rotational force of the rotor is transmitted to the drum shaft.

In addition, the rotor 44 is provided with a cooling unit 200. In particular, the cooling unit may be provided in the base 212 of the rotor frame 210. The cooling unit is provided to cool the stator 42 by generating an air flow during the rotation of the rotor frame 210.

The cooling unit 200 may include a blade 217 that directly generates a flow of air during rotation and a cooling hole 218 through which air is introduced or discharged. Detailed description of the cooling unit 200 will be described later.

In addition, the hub portion 213 may be provided with a coupling hole 214 for coupling the aforementioned connector, or a positioning groove 215 for determining the position of the connector first.

The rotor 44 accommodates the stator 42 therein, and rotates with respect to the stator 42 through interaction with the stator 42. Of course, the rotational force of the rotor is coupled to the rotor frame 210 is transmitted to the drum shaft to rotate integrally.

In the present invention, it is preferable to use a coil made of an aluminum core wire instead of a conventional copper coil. This can significantly reduce manufacturing costs.

However, as described above, the coil made of aluminum should have an effective cooling structure because the calorific value is larger than that of the copper coil. In addition, since it is preferable to be controlled to allow dehydration in both directions, it is preferable to have the same rotational characteristics and cooling characteristics regardless of the rotational direction. In addition, even when washing or rinsing is performed in step motion or scrub motion, since a large load may be issued to the motor regardless of the rotation direction, it is desirable to have the same and effective cooling characteristics regardless of the rotation direction.

According to the research results of the present inventors, it was found that the cooling effect due to the air flowing into the rotor through the cooling hole is greater. This will be described with reference to FIGS. 6 and 7. 6 and 7 show the results of experiments in the cooling effect of the stator by the rotation of the rotor in the rear of the rotor and the blade is formed to be symmetrical only in one direction. 6 and 7 are formed to protrude into the rotor.

As shown in FIG. 6, when the rotor rotates in the counterclockwise direction, it can be seen that air is introduced into the rotor from the rear of the rotor through the cooling hole. Similarly, when the rotor rotates in a clockwise direction as shown in FIG. 7, it can be seen that air flows out of the rotor to the rear of the rotor. Comparing them, it can be seen that the cooling effect of the stator is further improved when air is introduced into the rotor from the rear of the rotor. This is because the cool air from the outside of the rotor flows into the rotor through the cooling hole of the base to facilitate heat exchange with the stator. On the contrary, the air flows from the gap between the stator and the rotor or from the slot of the stator, and the air flows out of the rear of the rotor. That is, in the case where air is introduced into the rotor through the cooling hole, the temperature difference may be larger than the reverse case.

It can also be seen that the flow of air generated by the blades directly heat exchanges with the stator. In other words, it can be said that the air flow rate is faster than the case in which the air is introduced through the cooling hole than the reverse case.

Therefore, the cooling effect when rotating in the counterclockwise direction is excellent through Figures 6 and 7, it can be seen that the cooling effect is very low when rotating in the clockwise direction. That is, it can be seen that the cooling effect is superior to the case where air is introduced into the rotor through the cooling hole.

Reflecting the experimental results, it is necessary to ensure that a sufficient amount of air is introduced into the rotor through the cooling holes. This also needs to be ensured regardless of the direction of rotation.

5 and 8, the rotor will be described in detail with respect to the cooling unit 200. FIG. 8 is a schematic cross-sectional view taken along line AA ′ of FIG. 5.

The base 212 of the rotor is provided with a plurality of cooling units 200. The cooling section is configured to cool the stator 42.

The cooling unit 42 includes a blade 217 and a cooling hole 218 for generating a flow of air when the rotor rotates, that is, when the rotor frame rotates. Specifically, the cooling unit 42 includes a pair of blades 217a and 217b and cooling holes 218 through which air is introduced and discharged in the axial direction when the blades rotate.

Eight cooling parts are shown in FIG. 5, and the number of cooling parts may be increased or decreased. However, the number of cooling parts is related to the height of the blade and the distance that air can flow in the circumferential direction inside the rotor. As the number of cooling units increases, the height of the blade may be shortened, and thus air may not be sufficiently introduced to the stator. In addition, as the number of cooling sections decreases, there is a fear that the air flow component in the circumferential direction of the rotor decreases. Therefore, in view of this point, it is preferable that the number of cooling parts is 8-14.

The cooling units are preferably formed to be symmetrical with each other in the circumferential direction. In addition, the blade 217 and the cooling hole 218 constituting one cooling unit 200 is also preferably formed to be symmetrical with each other in the circumferential direction.

Here, the blade 217 and the cooling hole 218 is preferably formed to have the same vibration characteristics or rotation characteristics regardless of which direction the rotor frame rotates. Therefore, the same cooling characteristic can be obtained regardless of which direction the dehydration proceeds.

More specifically, as shown in FIG. 8, the cooling unit 200 has a first blade 217a, a first cooling hole 218a, a base 212, and a second cooling hole 218b along the circumferential direction. The second blade 217b may be formed in order. Here, the first blade 217a may be provided on the left side of the first cooling hole 218a, and the second blade 217b may be provided on the right side of the second cooling hole 218b. The first blade 217a and the first cooling hole 218a are formed symmetrically with the second cooling hole 218b and the second blade 217b based on the center line 220. The center line 220 extends in the radial direction from the center of the rotor as a virtual line. In addition, a plurality of center lines may be provided, and thus, a plurality of cooling units 200 may be formed. As a result, the cooling unit 200 is formed in plural at regular intervals along the circumferential direction.

Thus, the same cooling characteristic can be obtained regardless of whether the rotor frame rotates clockwise or counterclockwise. Of course, the vibration characteristics are the same regardless of the rotation direction of the rotor frame.

The blade 217 generates a flow of air. The inflow and outflow of air is made through the cooling hole 218. More specifically, the blade 217 and the cooling hole 218 are provided in pairs, respectively. Due to the characteristics of the cooling unit 200, when the inflow of air occurs in the first cooling hole, the outflow of air occurs in the second cooling hole. On the contrary, when inflow of air occurs in the first cooling hole, outflow of air occurs in the second cooling hole. Therefore, the outflow and inflow of air occur at the same time through the cooling hole provided in the base regardless of the dehydration rotation direction. In other words, regardless of which direction it rotates, air is introduced into the rotor through the cooling hole as much as possible, thereby effectively cooling the stator. In addition, since the formation pattern of the cooling unit is the same along the circumferential direction regardless of the rotation direction, the rotation characteristics are the same. Therefore, control is easy and manufacture becomes easy.

The blade 217 may be integrally formed with the base 212 at the edge of the cooling hole 218. That is, a part of the base may be cut while forming a cooling hole through a lancing process, and the blade may be raised to form the blade. Therefore, the blade may be formed to protrude perpendicularly from the base in the stator direction.

Here, it is possible to further increase the protruding height of the blade in order to further increase the flow of air. However, this height has some limitations. This is because the distance from the rotor to the stator must be maintained. In the same context, it is possible to increase the area of the cooling hole when the height of the blade is constant. That is, it may be desirable to form an area of the cooling hole more than the area generated by the blade so that the air flows in and out more smoothly.

The rotor frame 210 needs to be fixed to a processing apparatus for press working or lancing processing. Of course, in order to magnetize after the magnet 216 is formed in the rotor frame, it needs to be fixed to the magnetizing device. To this end, it is preferable that a fixing hole 222 for fixing is formed in the rotor frame, especially the base. Here, the fixing hole is preferably formed in the cooling hole 218. Accordingly, the fixing hole 222 widens the area of the cooling hole 218 to further enhance the cooling effect.

In the present embodiment, when air flows into the rotor through the first cooling hole 218a formed in one cooling unit 200, air flows out of the rotor through the adjacent second cooling holes 218b. This is caused by the circumferential air flow inside the rotor due to the first blade 217a and the second blade 217b, and the inflowed air moves in the circumferential direction to exchange heat with the stator and flow out. Thus, heat exchange can be sufficiently achieved through this circumferential flow of air. This means that sufficient heat exchange time is ensured until cold air is introduced and discharged.

To this end, the base 212 is preferably blocked between the first cooling hole 218a and the second cooling hole 218b so as to remain intact. That is, it is preferable that a sufficient distance is secured between the first cooling hole and the second cooling hole. Therefore, the air flow in the direction of the rotation axis (drum axis) on both sides with respect to the center line 200 is opposite to each other.

In addition, the cooling unit 200 should be symmetric regardless of the direction of rotation. Therefore, the first cooling hole is provided at a position symmetrical with the second cooling hole with respect to the center line. Similarly, the first blade 217a is provided at a position symmetrical with the second blade 217b with respect to the center line. In this embodiment, the blade 217 is provided near one side edge or one side edge of the cooling hole 218. More specifically, the center line 200 is provided near the outer edge or the outer edge.

Here, the blade 217 is very preferably provided to protrude upward in the rotation axis direction. That is, the base 212 is preferably provided to protrude inward of the rotor. This is because the stator to be cooled is provided inside the rotor, and therefore it is desirable to directly generate an air flow in the circumferential direction from the inside of the rotor.

On the other hand, although not shown in Figure 5, it is preferable that the area of the cooling hole 218 is formed to increase in the radial direction. For example, it may be formed so that the circumferential width of the cooling hole is gradually increased toward the radial direction. It may also be formed such that the circumferential width of the radially outer portion is greater than the circumferential width of the radially inner portion. Like the cooling hole 218, the protruding height of the blade 217 may be formed to be higher at the radially outer side than the radially inner side. This geometric feature is related to the radius of rotation. The larger the radius of rotation, the larger the circumference, the greater the distance traveled during rotation. As a result, by increasing the height of the blade in the radially outer side, or by increasing the area of the cooling hole, it is possible to further activate the flow of air.

FIG. 9 is a graph showing cooling performance of the rotor shown in FIG. 4, and FIG. 10 is a graph showing cooling performance of a rotor having a larger cooling hole area in the radially outer side.

As shown in FIG. 9, when the rotor is rotated in the counterclockwise direction, it can be seen that inflow and outflow of air occur in the cooling unit. That is, it can be seen that cold air flows into the rotor from the outside of the rotor through the cooling holes on the left side, and hot air inside the rotor flows out of the rotor through the cooling holes on the right side. In addition, it can be seen that the temperature distribution of the stator is significantly improved due to the inflow and outflow of air.

Then, when the rotor is rotated in the clockwise direction, air flow is generated in the same manner. However, air will flow through the cooling hole on the right and air will flow through the cooling hole on the left.

Therefore, it can be seen that as the rotor rotates, outflow and inflow of air are generated through the cooling holes, thereby effectively cooling the stator. This is because cold air flows in and sufficiently heat exchanges with the stator inside the rotor, and then hot air flows out of the rotor.

9 and 10, it can be seen that the temperature distribution in the cooling holes shown in FIG. 10 is concentrated. That is, it can be seen that in the cooling holes in which the inflow of air occurs, cold air is evenly introduced in the entire cooling hole, and in the cooling holes in which the opposite high air flows out, the hot air is evenly discharged in the entire cooling hole. Therefore, it can be seen that increasing the circumferential width of the cooling hole further improves the cooling performance more effectively. In particular, it can be seen that it is desirable to further increase the circumferential width in the radially outer side.

Hereinafter, a rotor of another embodiment will be described in detail with reference to FIG. 11.

The rotor of this embodiment may be the same as the embodiment shown in FIG. 4 except for the cooling unit 300. That is, only the shape of the cooling unit 300 may be different from the above-described embodiment. This embodiment may be easily described with reference to FIG. 11 as another example of the AA ′ cross-sectional view of FIG. 4.

As shown in Fig. 10, in this embodiment, the position of the blade is different from the above-described embodiment.

Cooling holes 318a and 318b are formed on both sides of the center line 200 so as to be symmetrical with each other. In addition, blades 317a and 317b are provided at inner edges of the cooling holes based on the center line 200.

In this embodiment, the inflow and outflow of air is generated in the cooling holes 318a and 318b as the rotor rotates. For example, when rotating to the left, air flows out through the first cooling hole 318a and air flows through the second cooling hole 318b. And if it turns to the right, air will flow in the opposite direction. Therefore, the same air flow is generated irrespective of the rotational direction, so that vibration and noise variation along the rotational direction can be minimized. In addition, the cooling characteristics can be satisfied regardless of the rotation direction.

Hereinafter, a rotor of another embodiment will be described in detail with reference to FIG. 12.

In the above two embodiments, the air flow in the circumferential direction is generated, and the pressure deviation results in the inflow and outflow of air in the direction of the rotation axis. However, in this embodiment, not only generates the air flow in the circumferential direction directly through the blade, but also directly generates the air flow in the rotational axis direction.

To this end, the cooling unit 400 includes a first cooling hole 418a and a second cooling hole 418b to be symmetrical to both sides with respect to the center line 200. In addition, the blade is inclined at the outer edge of the center line of the cooling holes. That is, the first blade 417a is provided near the outer edge or the edge of the first cooling hole 418a, and the second blade 417b is provided near the outer edge or the edge of the second cooling hole 418b.

Here, the blades are preferably protruded inclined toward the center line 200. That is, it is preferable to protrude in the stator direction. Due to the shape and positional characteristics of the cooling unit, the air flows directly in the circumferential direction and the rotation axis direction by the rotation of the rotor. Therefore, it is possible to generate the air flow in the direction of the direct rotation axis to facilitate the inflow and outflow of air to further improve the cooling performance.

Meanwhile, in order to further smoothly flow the air, the third blade 419a and the fourth blade 419b may be provided. The third blade is provided to be diagonally symmetrical with the first blade 417a near one side edge or one side edge of the first cooling hole 418a. The fourth blade is disposed to be symmetrical with the second blade 417b near one side edge or one side edge of the second cooling hole 418b.

The combination of the cooling holes and the blades causes the flow of air, while guiding the flow of air to cool the stator more effectively.

Here, the guide blade 420 may be provided to guide the flow of air more effectively. The guide blade is preferably provided in at least one of the radially outer edge or the inner edge of the cooling hole in the circumferential direction.

4 and 5, it can be seen that the radial width of the cooling hole corresponds to the portion of the coil winding in the stator. This is because the largest heat is generated in the windings 121 and 131 to which the coil is wound, so as to effectively cool this portion. In addition, the air introduced in the direction of the rotation axis passes through the winding part is preferably heat exchange is made. And, it is necessary to minimize the flow of air in the direction of the rotation axis through the gap between the magnet 216 and the tooth (112). This is because these air flow components can cause noise and vibration. And, to allow the air to flow into the winding portion as much as possible.

To this end, it is very preferable that the guide blade 420 is provided. Through this, the air introduced through the cooling hole is concentrated in the winding part, and the air introduced into the gap can be minimized.

On the other hand, the guide blade 420 is preferably formed integrally with the blades (417a, 417b, 419a, 419b). The guide blade 420 may be integrally formed through the lancing process. Since the blades protrude in an inclined form, the base portion is tensioned to form the guide blade 420 integrally.

1 is a cross-sectional view of a washing apparatus that can be applied to the present invention;

2 is a schematic diagram illustrating step motion in chronological order;

3 is a schematic diagram illustrating the scrub motion in chronological order;

4 is an exploded perspective view of the stator;

5 is a perspective view of a rotor according to an embodiment of the present invention;

6 and 7 are graphs showing cooling performance of a conventional rotor;

8 is a cross-sectional view of FIG. 5 AA ′;

9 and 10 are graphs showing cooling performance of a rotor according to an embodiment of the present invention;

11 is a sectional view taken along line AA ′ of the rotor according to another embodiment of the present invention;

12 is a sectional view taken along line AA ′ of the rotor according to another embodiment of the present invention.

Claims (18)

Tub; A drum rotatably provided in the tub; A motor including a stator fixed to the rear wall of the tub, a rotor rotating outside the stator to rotate the drum, and a cooling unit provided at the base of the rotor to generate air flow during rotation to cool the stator; And It includes a controller for controlling the dehydration in the drum by rotating the motor irrespective of the rotation direction of the motor, The cooling unit, A first cooling hole and a second cooling hole provided to be symmetrical with each other at a predetermined distance from both sides with respect to a center line extending in a radial direction from the center of the base; A first blade configured to generate air flow in an inner circumferential direction of the rotor and allow air to flow into the rotor through the first cooling hole; And And a second blade provided to be symmetrical with the first blade based on the middle wire to allow air to flow out of the rotor through the second cooling hole. The method of claim 1, Washing device, characterized in that provided with a plurality of the cooling unit in the circumferential direction of the base. The method of claim 2, The formation pattern of the cooling holes and the blades in the clockwise direction of the base is the same as the formation pattern of the base in the counterclockwise direction. The method of claim 3, wherein The first blade is located near the edge or the edge of the first cooling hole, the second blade is laundry machine, characterized in that located near the edge or the edge of the second cooling hole. The method of claim 4, wherein Washing apparatus, characterized in that the first blade and the second blade is located on the inside with respect to the center line. The method of claim 5, Washing apparatus, characterized in that the first blade and the second blade is located on the outside with respect to the center line. The method according to claim 5 or 6, And the blades protrude vertically from the base. The method of claim 3, wherein Washing apparatus, characterized in that between the cooling unit and the cooling unit is provided with embossing for reinforcing the strength of the base. The method of claim 3, wherein The cooling hole washing machine, characterized in that formed extending in the radial direction of the base. The method of claim 3, wherein Washing device, characterized in that the cooling hole is widened the area of the cooling hole, a fixing groove for fixing when the rotor is manufactured. The method of claim 1, The stator is a motor, characterized in that the coil of aluminum material is wound. Tub; A drum rotatably provided in the tub; A motor including a stator fixed to the rear wall of the tub, a rotor rotating outside the stator to rotate the drum, and a cooling unit provided at a base of the rotor to generate air flow during rotation; And It includes a controller for controlling the washing or rinsing proceeds in the drum by repeating the sudden stop by the rotation of the motor and reverse phase braking, The cooling unit, A first cooling hole and a second cooling hole provided to be symmetrical with each other at a predetermined distance from both sides with respect to a center line extending in a radial direction from the center of the base; A first blade configured to generate air flow in an inner circumferential direction of the rotor and allow air to flow into the rotor through the first cooling hole; And And a second blade provided to be symmetrical with the first blade based on the center line so that air flows out of the rotor through the second cooling hole. 13. The method of claim 12, Washing device, characterized in that provided with a plurality of the cooling unit in the circumferential direction of the base. The method of claim 13, The cooling unit is characterized in that the symmetrical with each other along the circumferential direction of the base. 13. The method of claim 12, The cooling unit washing apparatus characterized in that it comprises a cooling hole formed at a predetermined distance apart from both sides from the center line. 13. The method of claim 12, The stator is a washing device, characterized in that the coil of the aluminum material is wound. 13. The method of claim 12, The protrusion height of the blade is higher in the radially outer than in the radially inner washing apparatus. 13. The method of claim 12, Washing apparatus, characterized in that the circumferential width of the cooling hole is larger in the radially outer side than in the radially inner side.

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